Programmable devices such as FPGAs (field programmable gate arrays) are devices that can be designed and programmed via programming tools to operate in a wide variety of applications. Programmable devices include logic elements and interconnect resources that can be configured as necessary to operate in a particular application. The logic elements and interconnect resources are configured in collections known as logic blocks, which often times perform a specific function. Programmable devices also typically include other resources such as Random Access Memory (RAM) and other predefined blocks of logic such as a Digital Signal Processor (DSP), a Central Processing Unit (CPU), adders, multipliers, etc. During operation of the programmable device, the logic blocks and other resources are often shared by multiple logic elements.
Designs are typically partitioned into separate functional modules that include many logic blocks. Some of the functional modules may be purchased or licensed from a vendor for integration with other functional modules into the programmable device. These intellectual property modules often have certain rights and restrictions. In addition, many applications require a certain degree of system security and integrity. Functional modules employed in these types of applications have stricter security and integration requirements than those that are not since weaknesses and vulnerabilities can compromise the security and integrity of the system that they serve.
Many applications require secure programming and operation of programmable logic devices. For example, in certain applications, it is necessary to reprogram or upgrade a functional module regardless of whether the programmable device is operating or not. During operation of the programmable device, it may also be necessary to enable and/or disable different functional modules without affecting other functional modules. Also, suppliers of functional modules need to protect their intellectual property when integrated with other functional modules in a third-party design. There may be a need to identify and be compensated for each instance or use of a vendor's intellectual property. These and other security and system integrity functions present various challenges during different phases of programmable device development and use. Security breaches can occur during the design, programming and operation of a programmable device absent sufficient mechanisms for protecting the functional modules included in the device.